Installation (cont.), Maintenance – Xylem MM 317C Models 21 & 221 Mechanical Water Feeders User Manual

Page 4

INSTALLATION (cont.)

a. Remove Feeder from Tank. Turn off the water

supply and drain the tank below the level of the
feeder flange. If fluid is heated, allow system to
cool to 80°F (27°C) before disassembly.
Disconnect the piping above the strainer assem-
bly. Remove the six (6) mounting bolts and lift off
the feeder from the tank.

b. Remove Valve Assembly. Remove float and

rod from the float arm of the valve linkage.
Unscrew the two (2) bolts from the strainer body
at the bottom of the valve assembly. Unscrew
the four (4) bolts from the valve body at the bot-
tom of the valve housing bracket. Pull the valve
assembly from the housing in an arcing move-
ment to clear the float arm from the interior.

c. Reassemble with new Valve Assembly.

Position the new valve assembly with new
gasket, float arm first, into the housing. Hand
secure the four (4) bolts and tighten to 16 ft/lbs.
Replace the strainer body and new gasket using
the two (2) bolts. Tighten to 16 ft/lbs. Reattach
the float and rod onto the float arm and hand
tighten.

d. Replace Feeder on Tank. Replace the assem-

bly and new gasket onto the tank flange. Tighten
the six (6) bolts to 16 ft/lbs. Reconnect the
piping and restore water supply. Check for prop-
er closing level and leakage before leaving the
jobsite.

Note: Use new gaskets; make sure all gasket
surfaces are clean.

21 Series - Replacement Valve Assembly (SA21-6)

Housing Gasket

Housing

SA21-6

Replacement

Valve

Strainer

Assembly

MAINTENANCE:

• Blow down tank weekly during heating season.

Blow down may have to be more frequent
depending on local water conditions and the
amount of make-up water.

• Clean strainer at least twice during heating

season. Cleaning may have to be more frequent
depending on local water conditions and the
amount of make-up water.

• Replace control every 15 years.

Xylem Inc.

8200 N. Austin Avenue

Morton Grove, Illinois 60053

Phone: (847) 966-3700

Fax: (847) 965-8379

www.xyleminc.com/brands/mcdonnellmiller

McDonnell & Miller is a trademark of Xylem Inc. or one of its subsidiaries.